An actuation transmission mechanism comprising a transmitting member that is pivotably supported to pivot in at least one driving direction from a predetermined initial position to be capable of transmitting its pivoting motion to a transmitted member that is pivotably supported in the vicinity of the transmitting member to pivot in at least one driven direction from a predetermined driven initial position, wherein the transmitting member has a formation such that when the transmitting member pivots from the initial position in the one driving direction, the transmitting member abuts against the transmitted member to make the transmitted member pivot in the one driven direction from the driven initial position to a predetermined detection position, and thereafter, though the transmitting member subsequently pivots in the one driving direction further, the transmitting member does not make the transmitted member pivot overly to a large extent in the one driven direction from the detection position.